Illumination devices are used in various applications. The illumination device may be, for example, a BLU (backlight unit) of a display such as an LCD (liquid crystal display), a television, a computer, a mobile phone, a smart phone, a personal digital assistant (PDA), a gaming device, an electronic reading device or a digital camera. Besides, the illumination device can be used for indoor or outdoor lighting, stage lighting, decorative lighting, accent lighting or museum lighting, and the like, as well as special wavelength lighting required for horticulture and biology.
A typical illumination device is, for example, one used as a BLU of a LCD, and the like, and there is a device which emits a white light by combining phosphors such as a blue LED (Light-emitting Diode) and a YAG (Yttrium aluminum garnet).